1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Sindrei [870]
2 years ago
10

On your first day at work as an electrical technician, you are asked to determine the resistance per meter of a long piece of wi

re. The company you work for is poorly equipped. You find a battery, a voltmeter, and an ammeter, but no meter for directly measuring resistance (an ohmmeter). You put the leads from the voltmeter across the terminals of the battery, and the meter reads 13.0 V. You cut off a 20.0 m length of wire and connect it to the battery, with an ammeter in series with it to measure the current in the wire. The ammeter reads 7.60 A. You then cut off a 40.0 m length of wire and connect it to the battery, again with the ammeter in series to measure the current. The ammeter reads 4.50 A. Even though the equipment you have available to you is limited, your boss assures you of its high quality: The ammeter has very small resistance, and the voltmeter has very large resistance. What is the resistance of 1 meter of wire?
Physics
1 answer:
Lostsunrise [7]2 years ago
3 0

Answer:

0.06\Omega/m

Explanation:

Firstly, when you measure the voltage across the battery, you get the emf,

E = 13.0 V

In order to proceed we have to assume that the voltmeter offers no loading effect, which is a valid assumption since it has a very high resistance.

Secondly, the wires must be uniform. So the resistance per unit length is constant (say z). Now, even though the ammeter has very little resistance it cannot be ignored as it must be of comparable value/magnitude when compared to the wires. This is can seen in the two cases when currents were measured. Following Ohm's law and the resistance of a length of wire being proportional to it's length, we should have gotten half the current when measuring with the 40 m wire with respect to the 20 m wire (I=\frac{V}{R}). But this is not the case.

Let the resistance of the ammeter be r

Hence, using Ohm's law we get the following 2 equations:

\frac{13}{20z+r} =7.6   .......(1)

\frac{13}{40z+r} =4.5     ......(2)

Substituting the value of r from (2) in (1), we have,

13=152z+7.6\times\frac{13-180z}{4.5}

which simplifying gives us, z=0.0589\Omega/m\approx0.06\Omega/m (which is our required solution)

putting the value of z in either (1) or (2) gives us, r = 0.5325 \Omega

You might be interested in
A school bus has a mass (including the driver and passengers) of 1.64 times 10^4 kg and is driving north at a speed of 15.2 km/h
Butoxors [25]

Answer:

Explanation:

Given

mass of bus along with travelers travelling in North direction is m_1=1.6\times 10^4 kg

speed of bus towards North v_1=15.2 km/h\approx 4.22\ m/s

mass of bus travelling in South direction is m_2=1.578\times 10^4 kg

speed of bus v_2=12.2 km/h\approx 3.38\ m/s

mass of each Passenger in south moving bus m_0=64.8 kg

Momentum of North moving bus

P_1=m_1\times v_1

P_1=1.6\times 10^4\times 4.22

P_1=6.768\times 10^4 kg-m/s

Momentum with south moving bus

P_2=m_2\times v_2+n\cdot m_0\times v_2

P_2=(1.578\times 10^4+n\cdot 64.8 )\cdot 3.38

For total momentum to be towards south

P_2-P_1 should be greater than 0

thus for least value of n

P_2=P_1

(1.578\times 10^4+n\cdot 64.8 )\cdot 3.38=6.768\times 10^4

1.578\times 10^4+n\cdot 64.8=2.0023\times 10^4

n=\frac{4243.6686}{64.8}=65.48\approx 66    

5 0
3 years ago
How is velocity and instantaneous speed alike
allsm [11]
<span>velocity is defined as the rate of change of displacement irrespective of the length of the path travelled while speed is the average rate of covering distance. but in the liming case where the instantaneous velocity is given as v=dx/dt where dx is the small displacement in a small interval dt, both the speed and velocity have the same magnitude and the direction of velocity is the direction of the tangent to the corresponding displacement-time curve.</span>
5 0
3 years ago
7.
Usimov [2.4K]

Answer:

A

Explanation:

7 0
2 years ago
Read 2 more answers
Means/end analysis involves:_________
polet [3.4K]

a. a gradual approximation to the final solution

Explanation:

Means/end analysis is a process that involves creation of an end goal to enable the identified means to apply.

In this techniques sub-goals are formed to eliminate the challenges faced in application of a selected operator.

It starts by identifying a predetermined goal which is followed by actions that will led to the goal.

Learn More

Mean/end analysis : brainly.com/question/1213695

Keywords : mean, end, analysis

#LearnwithBrainly

4 0
2 years ago
What is the attractive force between all matter in the universe?
kvv77 [185]
The attractive force between all matter in the universe is gravity.
4 0
3 years ago
Read 2 more answers
Other questions:
  • Which best describes the transition from gas to liquid?
    10·2 answers
  • If you run 12m/s for 15 minutes, how far will you go explain?
    15·1 answer
  • A projectile is fired with an initial speed of 51.2 m/s at an angle of 44.5 degrees above the horizontal on a long flat firing r
    14·1 answer
  • 1. A car with a mass of 1,500 kilograms is moving around a circular curve at a uniform velocity of 16 m/s. The curve has a radiu
    7·2 answers
  • Raising the temperature of a gas will increase its pressure if the volume of the gas
    7·1 answer
  • How do you find the period
    5·1 answer
  • A 92-kg fullback moving south with a speed of 5.8 m/s is tackled by a 110-kg lineman running west with a speed of 3.6 m/s. Assum
    11·1 answer
  • Why are isotopes not shown on the periodic table
    11·1 answer
  • Can anybody help me it says, Model the force that would cause each velocity change.
    5·2 answers
  • The range of diameters and luminosities displayed by elliptical galaxies is ____.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!